Unix timestamp converter
Convert Unix seconds or milliseconds to and from explicit-zone ISO dates.
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Result
Ready when you areEnter your input and run the tool to see your result here.
Good to know
Unix time starts at 1970-01-01T00:00:00Z. Include Z or an offset such as +09:00 in date input. Output dates are UTC with millisecond precision.
Operation: to-unix Timestamp unit: seconds Input: 2024-01-01T00:00:00Z
Understand and use your results
Compare Unix values from logs or APIs with readable dates. Mixing seconds and milliseconds yields very different dates, so verify the input unit first.
How to use it
- Choose the direction and select seconds or milliseconds.
- Include a time zone such as Z or +09:00 when entering a date.
Worked example
1970-01-01T09:00:00+09:00 → seconds
0
09:00 at UTC+09:00 is midnight UTC, the Unix epoch. The instant is independent of the device time zone, and ISO output is shown in UTC.
Why must a date include a time zone?
2024-01-01T00:00:00 alone does not say which region’s midnight is intended. Dates without a zone are rejected rather than guessed. Invalid calendar dates and out-of-range times must also be corrected.